The MAST Immunodiagnostic Test System was developed to provide a comprehensive, simple means for the in vitro measurement of multiple antigens or antibodies. The first commercial application of the MAST system incorporates several novel features for cost-effective diagnosis of IgE-mediated allergy in a clinical laboratory or a physician's office. The basis of the MAST system is a unique analytical test chamber, which contains cellulose thread as the solid-phase matrix and allows multiple test results from a single assay. This test chamber incorporates both positive and negative controls and requires no volume-dependent pipetting steps. Immunographic exposure onto high-speed Polaroid instant film allows for quantifying results with an automatic recording infrared-transmittance densitometer. Test results are easily interpreted by using a patient test record provided with the system. The MAST system greatly simplifies testing for allergen-specific IgE, while retaining specificity and sensitivity. Currently, with the MAST system one can simultaneously measure picomoles of allergen-specific IgE in up to 35 different allergen classes. In addition to allergy testing, the MAST technology is applicable to other immunodiagnostic profiles.